1625055778665 has 48 divisors (see below), whose sum is σ = 3079498758336. Its totient is φ = 786196598400.

The previous prime is 1625055778663. The next prime is 1625055778699. The reversal of 1625055778665 is 5668775505261.

1625055778665 is a `hidden beast` number, since 1 + 6 + 2 + 5 + 0 + 557 + 78 + 6 + 6 + 5 = 666.

It is not a de Polignac number, because 1625055778665 - 2¹ = 1625055778663 is a prime.

It is not an unprimeable number, because it can be changed into a prime (1625055778663) by changing a digit.

It is a polite number, since it can be written in 47 ways as a sum of consecutive naturals, for example, 3332479 + ... + 3788868.

It is an arithmetic number, because the mean of its divisors is an integer number (64156224132).

Almost surely, 2^{1625055778665} is an apocalyptic number.

1625055778665 is a gapful number since it is divisible by the number (15) formed by its first and last digit.

It is an amenable number.

1625055778665 is a deficient number, since it is larger than the sum of its proper divisors (1454442979671).

1625055778665 is a wasteful number, since it uses less digits than its factorization.

1625055778665 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 7121830 (or 7121827 counting only the distinct ones).

The product of its (nonzero) digits is 105840000, while the sum is 63.

The spelling of 1625055778665 in words is "one trillion, six hundred twenty-five billion, fifty-five million, seven hundred seventy-eight thousand, six hundred sixty-five".